We heard that Demi Moore was partyin' hAArd at the Art.sy and Chanel BBQ in Miami Wednesday night, and girl was even rumored to be hanging with her 26-year-old Vito Schnabel…

But it seems that Dem was also grindin' her cougar ass up on ANOTHER man during the event, the seXXXy Lenny Kravitz (above)!

One party onlooker reveals:

"[Demi] was most ready to party than anyone else in the room."

Demi was apparently acting VERY hyper all evening — she was seen clutching an energy drink most of the night — and constantly cozied up to Lenny on the couch while she wan't trying to stick her bum-bum in his face.

Ashton Kutcher's ex-ladylove also schmoozed with George Clooney's girlfriend Stacey Kiebler, and was photographed hanging on her arm while the party was wrapping up.

Well, we're glad Demi is obviously letting loose, and girl seemed to be having a ballz-to-the-wall good time…

But we hope Dems didn't have a little TOO much fun, you know, indulging in certain alcoholic/druggy poisons and whatnot!

And she looks great for her age, but damnit, someone needs to give her some dance and rhythm lessons cause girl is always angular and knock kneed when she dances. Bitch did the same white girl from the 80's dance at that Snoop concert a couple years back.

That's just sad. My heart breaks for her. Notice nobody else is dancing and she's making an ass out of herself. She needs to focus on her kids and finding a man to grow old with. Not a child that will leave her in 5yrs for a younger woman. A man atleast 40

Guess this is what happens when you never had a lot of talent to begin with, but were really good at courting fame. I bet Demi never thought she relied on her looks, but the evidence is stark that she did.

You old farts… Nothing wrong with a mature woman with a tight ass body swinging those hips around. I bet everyone else in that room think their too cool to be having that type of fun. Get a life you biotches, learn to enjoy life and let loose at a party!!

RE:Kappuhcheenoh,what gives you the right to say she has no acting talent.Where has your head been? She has more talent then alot of those so called overpaid bimbos out there now.Look at her soon to be ex, he suxs at it, hell he suxs at everything.I don't blame her if she wants to dance who cares, maybe she likes to dance.I don't see her grinding on Kravatz, Leave her the fuck alone, just coz she turned 50around don't mean she has to sit in a rocker and knit.She was a good Mom to her kids and now their grown up.As long as she feels good leave her alone.She has been hurt enough by her scum bag husband.I hope he is sterile and his little princess Mila has to have artifical insemination from another guy.Fix him for crushing her heart and cheating on her.He has to be the most uncaring cold heartiest dbag around.So all you nasty optionated people leave her be.

Sheesh ya'll act like because she's over 21 yrs old she can't do anything but stay at home and knit sweaters or babysitt her kids. There is nothing wrong with dancing your ass off and having fun and as for those remarking about her looks or age she um…looks a hell of a lot better then most men and women of every age I've seen. I doubt most of you look half as good as her. Online judgement is funnay!!!

Re: clara – I agree, people are ridiculous. They either think people can't do anything, but knit sweaters and babysit their kids all day after the age of 25 and when they do reach the age of 25+ they're usually to fat and jacked up to do anything other then stay at home and knit sweaters so they judge normal people for having fun and looking good. Demi is gooooooorgeous…go girl!

Re:Thank you Cher! You definitely get it.Am 55 and take very good care of myself.Not just for vanity, I keep my weight down because off health issue.But mainly so my husband will be proud of me.We have been married almost 38 yrs.I married him when I was 18.we still love each other so much.We have two grown kids a son and he has our little sweet grandson my daughter with our beautiful granddaughter.They both also are in very lovable happy marriages.Some people think they our my son &I daughter.Yes it does in a teeny sort of way make me feel good.But what make me feel blessed is they are all in good health.I guess I better get to the point.I get invited out with my daughter's freinds and yes we have some drink and dance.I don't find it sad by any means.Looks like a she is just having fun.Kutcher put her thru hell, crewed her up and spit her to the curb.Can you imagine the hurt and embrassment he did to her.She is trying to get her life back, because he missed her up so horribly.He acts like he never knew her.So yes you critical people keep up you nasty comments, because she was dancing.Oh my lets stone her to death.People are so cold.